Liquid masking compounds are not new. The principal ingredient thereof is a water-soluble polymer material that is formulated and applicable as a liquid and which readily dries to form a polymeric film. The film should not have a great affinity for the underlying surface so that it can readily be removed when desired by peeling away of the dry film or washing to dissolve the film which is simultaneously removed.
The patent literature does include films of this type. U.S. Pat. No. 5,186,978, for instance, is directed toward a liquid masking compound which comprises water, an aliphatic polyol such as polyvinyl alcohol, an alcohol and a surfactant. Methods protecting various surfaces are disclosed in conjunction therewith.
U.S. Pat. No. 5,183,688 discloses a so-called water-based resist material which comprises water, polyvinyl alcohol, isopropyl alcohol, a surfactant and cornstarch. This resist material is used in conjunction with applying advertising messages onto convex acrylic mirrored surfaces.
U.S. Pat. No. 5,026,597 is directed toward temporary protective coating comprising a water-soluble polymeric film and insoluble inert particles such as polyethylene and acrylic beads which act as spacers. Such coatings are applied to glass and polymeric sheet surfaces and the beads act as spacers when the sheets are stacked.
U.S. Pat. No. 4,222,922 is directed toward a warp size composition for polyester filaments which comprises polyvinyl alcohol, a cationic surfactant and a polyhydric alcohol plasticizer, such as glycerol.
While attempts have been made heretofore to formulate liquid masking compounds and protective coatings for a variety of purposes, the art has not provided a polyvinyl alcohol-based composition devoid of alcohol or other such volatile materials for use as a paint-masking film or for other purposes where it is desirable to apply the film as a liquid and subsequently remove the dried film by washing.